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Spiders reveal mercury pollution in waterbodies

Spiders living along lake shores can
predict mercury pollution, a study conducted at Texas Christian University
(Fort Worth) revealed.

Researchers examined
the transport of mercury through insects that spend part of their life in water
and part on land, and the effects fish predation of these insects has on
transport. Fish were found to reduce transport of mercury by larger insects,
but terrestrial spiders consume smaller insects, according to the abstract of a
recent report on the study.

Researchers studied 10 ponds, both with
and without fish, that had different levels of mercury contamination. They
found that the long-jawed orb weaver, a common shoreline spider, consumed small
aquatic insects, such as midges, that emerged from the ponds, according to a
Dick Jones Communications (Wooster, Ohio) news release. The spiders had average
mercury levels correlating to these small emergent insects, as well as to the
ponds where the insects lived. The spiders then are consumed by birds,
contributing to the spread of mercury contamination, the news release says.

Mercury contamination
in lakes often is monitored by sampling fish, but some waterbodies contain no
fish, and the fish-sampling process is time-intensive and expensive, the news
release says. Using terrestrial spiders to monitor waterbodies can help
scientists and environmental managers monitor an aquatic ecosystem regardless
of its fish population and has the potential to be a more efficient monitoring
method, the news release says.

A report on the study, “Effects of Fish on
Emergent Insect-Mediated Flux of Methyl Mercury Across a Gradient of
Contamination,” was published in the Feb. 5 issue of Environmental Science
& Technology.

Water, water everywhere, even on the moon

New
evidence shows water was present on the moon while it was forming. Traces of
water have been found within the crystalline structure of mineral samples taken
from the lunar highland upper crust. These samples were during the Apollo
missions, according to a University of Michigan (Ann Arbor) news release.

During
the past 5 years, research supporting the historical presence of water on the
moon has been accumulating. Previous research identified hydroxyl ions, which
contain one atom of hydrogen and one atom of oxygen, on the moon. For the
current study, researchers detected about 6 ppm of water, in the form of
hydroxyl groups, in grains of the samples of highland rock, the news release
says.

The
moon’s highland rocks were thought to have formed early in its history. This
provides evidence that the interior of the moon contained significant amounts
of water during its early molten state, before the crust solidified, the news
release says.

Findings
from the study, performed by researchers at the University of Notre Dame (South
Bend, Ind.), NASA, and the University of Michigan, was published in the Feb. 17
issue of Nature Geoscience.

Using solids from mines to remove phosphorus from wastewater

Residuals from acid mine drainage can be
used to remove phosphorus from agricultural and municipal wastewater, according
to research published in the journal Water, Air & Soil Pollution.

Acid mine drainage, which consists of acid
and dissolved metals, is produced when sulfide minerals associated with coal
and metal deposits are exposed to air and moisture. Drainage is neutralized
during remediation with such bases as limestone or lime, and iron-rich solids
form, according to a U.S. Geological Survey (USGS) news release.

For the study, a USGS researcher and IAP World Services (Cape Canaveral, Fla.) researcher
identified a new process that uses these solids to filter phosphorus from
wastewater. The researchers also found that the phosphorus can be stripped from
the residuals. The solids can be reused for additional treatment cycles, and
the phosphorus can be recycled into fertilizer, the news release says. The
technology reduces the need for solids disposal, decreases drainage treatment
costs, and prevents harm to aquatic ecosystems.

Map details environmental stresses of the U.S. Great Lakes

A new mapping project
tells the story of the U.S. Great Lakes’ environmental health. The
high-resolution spatial analyses maps identify locations and ranges of
environmental stresses affecting ecological services provided by the five
lakes.

A team led by
University of Michigan (Ann Arbor) researchers worked together on the Great
Lakes Environmental Assessment and Mapping project, according to a university
news release.

The team gathered
data and mapped 34 individual stressors for the region, which spans nearly 1448
km (900 mi). Stressors, mapped on the scale of 0.8 km (0.5 mi), include coastal
development, pollutants, fishing pressure, climate change, invasive species,
and toxic chemicals. To rank the importance of different stressors, the team
surveyed 161 researchers and natural resource managers from the area, the news
release says.

The Great Lakes
provides recreational and commercial ecosystem services, such as fishing,
boating, and beach use. By comparing maps of these services to maps of
stresses, researchers determined that often locations that provided the most
services were disproportionately stressed, the news release says. This provides
a scientific foundation to manage the ecosystem by providing planners and
government officials with information needed to prioritize areas to invest in
environmental restoration and natural resource protection, the news release
says.

The project, which
began in 2009 with funding from the Fred A. and Barbara M. Erb Family
Foundation (Bloomfield Hills, Mich.), will continue acquiring data to update
and map additional stressors, the news release says.

An article detailing
this effort was published Dec. 17 in the Proceedings of the National Academy
of Sciences. Read more at www.greatlakesmapping.org.